Device for sorting, dehydrating, or washing of suspensions of fibrous materials



Aug. 27, 1946. K. o. LINDGREN DEVICE FOR SORTING, DEHYDRATING, OR WASHING 0F SI SPENSIONS 0F FIBROUS MATERIALS F-iled. Feb. 4,1943 2 Sheets-Shet 1 INVENTOR= KARLOLOF LINDGREN a, ATTORNEYS.-

K. O. LINDGREN Aug. 27, 1946. 2,406,618

v DEVICE FOR SORTING, DEHYDRATING, OR WASHING 0F SUSPENSIONS OF FIBROUS' MATERIALS Filed Feb. 4, 1945 2 Sheets-She t 2 rill/fin rl/l/I/l/l/ 4 f I i Z I I I I Z ///////I/II//IlII/I/I INVENTOR agm m 9% Hum u MM m K Y v Patented Aug. 27,1946

mm OFFICE 4 'pEvIoEFoR-jsoR'riNG, DEHYDRATING, OR WASHING or :sUsPENsroNs or 'FIBROUS MATERIALS Karl OlofLindgreri, Djursholm,,Sweden,assignor to. AktiebolagetfA. Ekstroinsf'jMaskinaffar,

, Stockholm, Sweden, a joint-stockfcompanyof;

Sweden, and Nils Walfrid Jonsson,'Lidlngo',

Sweden Application February 4, 1943, Serial No. 474,652

' In Sweden January 13, 1942 a 2 Claims.

Vibrating screen members which are exclusively elastically mounted have of late been commonly used in the cellulose industry for sorting, dehydrating or washing of suspensions of fibrous material, and have proved-to be of great practical value. g

It has now appeared to be very advantageous to use according to the present invention an apparatus in. which in a stationary container a rotatably mounted screening drum is suspended in yokes supported by elastic members and adapted to be vibrated by rotation of two shafts actuating the yokes and carrying eccentric weights, and to transmit such motion to the drum.

An embodiment of the invention is illustrated in the accompanying drawings, in which Figs. 1 and 2 are two different side views of the device. Fig. 3 is a top view of the device. Fig. 4 is a section on line C--C in Fig. l.

A screening drum 2 is rotatably mounted in a stationary container I. The end portions of the drum traverse packings in the walls of the container. On one side of the drum there is to the container I connected an inlet 3 for the fibrous suspension, and on the other side of the drum the container is provided with a shutter 5 adjustable in the vertical direction by means of a lift device 4 Fibrous suspension can flow oil to an outlet 6 over the upper edge of said shutter 5, the drum thus having its major portion submerged in the liquid suspension the level of which is controlled by the upper edge of said shutter. At the bottom of the container I there is a valve 1, through which thicker impurities gathering on the bottom can be removed.

The ends of the drum are supported at each side by a yoke 8, and in the two yokes there are mounted the two shafts 9, laterally spaced from the central axis of rotation of the drum and preferably arranged symmetrically, one on each side of the drum. The yokes 8 with the shafts Srest on screw or helical springs [0. Each shaft 9 is provided with an eccentric weight or weights, and is driven via an elastic coupling by an electric motor H. to operate in time and preferably they may be driven by electric synchronized motors. A vibrating motion is imparted to the drum through the rotation of the eccentric weight shafts. One end of the drum is connected to an outlet conduit l2 opening above a conveying trough [3. The other end is closed. I

The drum may be connected with a drive device setting the drum in rotation. In other cases the motion impulses transmitted from the yokes The two rotatable shafts are adaptedto the drum may be such that thedrum does not only obtain a vibratory motion but is also caused to rotate, the vibratory motion cooperating with the actual friction and liquid resistances.

From the suspension charged into the container I liquid, possibly with some of the suspended material, passes through the screen shell of the drum into the interior of the drum, leaves throughth outlet l2 and further through the conveying trough l3, whereas fibrous suspension not passing through the screen surface leaves through the shutter 5 through the outlet 6.

In order to clean the screen shell of the drum a spraying pipe l4, which is connected to a conduit 15 for supplying washing liquid, extends along the screen shell at the top within the drum. At the spraying the material sticking to the outside of the drum will be led to a collecting chamber 16 provided above the container, from where it is discharged through a conduit IT.

The described device may be modified in several respects. The drum need not be cylindric but shaped in some other way, for example conical or polyhedric. The elastic suspension may be obtained in some other way than by screw springs.

The invention may also be carried out in such a way that the suspension is charged into a rotating screening drum at its one end, whereby the unscreened material leaves at the other end of the drum, and the screened liquid possibly together with fibrous material suspended therein, passes to a container surrounding the drum from where it is then discharged.

The invention is of particular importance in the manufacture of paper pulp but it may be used with advantage also in treating of other fibrous suspensions.

Having now described my invention, what I claim as new and desire to secure by Letters Patent is:

1. An apparatus for sorting, dehydrating or washing of liquid suspensions of fibrous material, particularly paper pulp, comprising a stationary container for a liquid suspension, a rotatably mounted screening drum mounted and arranged for having its major portion submergedin the liquid suspension inside said stationary container, two yokes outside the container one at each end of the drum arranged to support said drum, verti-v cally elastic members, each of said yokes being supported adjacent each end exclusively by said elastic members and adapted to be vibrated while s so supported, two rotatable shafts mounted in saidyokes and carrying eccentric weights for shafts in synchronism, said shafts being located one on each side of said drum, laterally spaced from the central aXis of rotation of the screening drum and'adapted, to transmit by the synchronous bodily movement of said shafts and yokes vibratory motion to said drum.

2. An apparatus for sorting, dehydrating or Washing of liquid suspensions of fibrous material, particularly paper pulp, comprising a stationary container for a liquid suspension, a rotatably mounted screening drum mounted and arranged for having its major portion submerged in the liquid suspension inside said stationary container, two yokes outside the container one at each end 4 of the drum arranged to support said drum, vertically elastic helical springs, each of said yokes being supported adjacent each end exclusively upon said springs and adapted to be vibrated while so supported, two rotatable shafts mounted in said yokes and carrying eccentric weights for vibrating the yokes, means for rotating the shafts in synchronism, said shafts being located one on each side of the drum, symmetrically spaced from the central axis oi rotation of said drum, and adapted'to transmit by the synchronous bodily movement oi said shafts and said yokes vibratory motion t sa d d um.

, KARL OLOF LINDGREN. 

